Apparatus for producing fibrous building boards



INVENTOR ATTORNEYS APPARATUS FOR PRODUCING 'FIBRQUS BUILDING BOARDS Filed June 4. 1959 July 2, 1963 G. J. VAN ELTEN 2 Sheets-Sheet 1 v W M "IIIlY/III Ghwak y 2, 1963 G. J. VAN ELTEN 3,096,227

APPARATUS FOR PRODUCING FIBROUS BUILDING BOARDS Filed June 4, 1959 2 Sheets-Sheet 2 United States Patent 3,096,227 APPARATUS FOR PRODUCING FIBROUS BUILDING BOARDS Gerrit J an van Elten, Haarkampstraat 10, Voorthuizen, Netherlands Filed June 4, 1959, Ser. No. 818,171 Claims priority, application Netherlands June 4, 1958 4 Claims. (Cl. 156-372) The present invention relates to an apparatus for producing building boards from wood wool, excelsior or similar fibre material in the form of elongated, elastically resilient, crooked strands, and a suitable binding agent, such as cement or magnesite.

Building boards of this type are in use where a light construction of the house, room or other accommodation' is required so that they must meet a plurality of requirements. First of all it is necessary for them not only to be uniform in strength, but also in weight and solidity throughout their surface. When they are fixed to parts of the building which shall not be plastered, for instance with the roof, it is important that the boards have sharp corners and edges. As building boards usually are fixed with nails their edges should be longitudin'ally reinforced for this purpose. Further, the fibre material together with the binding agent needs to be equally distributed over the surface of the boards, and the fibre must "be well interlaced to provide for a high degree of breaking strength and elasticity of the board.

At the same time, production of the boards is required to be practical and economical by providing simple and cheap forming plates and cutting working time down to a minimum.

The apparatus and methods known so far are not in conformity with all these requirements as, for instance, where they furnish uniform board weights this is achieved by too complicated a procedure and it is difficult to uniformly strew the material, over the surface or where a uniform board volume is provided the weight varies from one board to another.

It is one object of the invention to provide a continuous production of building boards from fibre material which meet all necessities and in which the deficiencies of the methods known in the art are avoided.

Another object of the invention is to provide uniform strength and weight of the boards also where fibre material and binding agent are irregularly supplied into the forming plates.

. one side wall removed;

FIG. 2 is a top view on a larger scale of the forming plates at the place the fibre material with its binding agent is scattered on to it;

FIG. 3 is a sectional view on a part of the apparatus, taken on the line AA of FIGS. 1 and 2 011 the scale of FIG. 2;

FIG. 4 is a sectional view on a part of the apparatus, taken on the line BB of FIG 1 on the scale of FIG. 2;

FIG. 5 is a sectional view, taken on the line C-C of FIG. 1 on the scale of FIG. 2;

3,096,227 Patented July 2, 1963 FIG. 6 is an elevation on an enlarged scale of the rear portion of the apparatus in FIG. 1;

FIG. 7 is a schematical representation of the system in which the conveyer belt drive is steered by the conveyer belt scales which weighs the material to be strewn on the mould plates;

FIG. 8 is a side view on a pile of building boards on forming plates with tight marginal rims;

FIG. 9 is a partial elevation of a difierent construction showing the part of the apparatus Where the material is strewn on the mould plates;

FIG. 10 is a top View of the part shown in FIG. 9, taken in its line DD;

FIG. 11 is a cross-section of a forming plate or belt;

FIG. 12 is a side view on a pile of building boards on forming plates with loose marginal rims.

Referring now to FIG. 1, the apparatus contains a conveyer belt balance I placed below a conveyer belt 16 and revolving in constant speed. The fibre material, which is supplied by a planar and thereafter mixed with a binding agent, such as cement or magnesite, is fed to this upper conveyer belt 16 where it is evenly distributed by means of a distributor wheel 14 revolving in arrow direction so that it can be continuously weighed on the conveyor belt balance 1.

A distributor wheel or device 2 is located below the conveyor belt balance 1 which revolves, for instance, in arrow direction and is partly covered at its lower side by a sheet iron plate 17. The distributor 2 throws the material into forming or mould plates, which are lined one next to the other upon a conveyer belt 34. The longitudinal margins of these mould plates consist of, for instance, rims 19, and their bases 18 may consist of planks or plywood. The plates 18, 19 move along with the conveyer belt 34. The several rims 19 are shorter than the base 18.

At the front end of the conveyer belt 34 an inclined guide shield 3 is provided having a surface which is conically rounded so that end which is next to the distributor Wheel 2. Rearwards it is continued in two planes symmetrically angular inclined against each other.

As to be seen from. FIG. 2, this hollow guide shield 3 contains two rolls 4 which are rotated in the direction of the arrows and are carried by levers engaged by a tension spring 23. The guide shield 3 guides the elongated fibers so that they drop upon the plates .18, 19 within the narrow spaces 5 (FIG. 2) located between the sides of the guide shield 3 and the rims 19; they also drop upon the portions of the rolls 4 extending outside of the guide shield 3. Thus the guide shield 3 prevents the fibers from dropping in the middle of the plates 18, 19. The function of the rolls 4 is in the lower portion of the mould to press the elongated fibers onto the marginal rims 19, whereby the lower marginal portion 6(see FIG. 3) becomes sharp and denser than the other portions 8 of the material supplied by the distributor, with which the marginal portion 6 unites. This device makes it possible to provide boards with compactly pressed edges containing an adequate number of elongated fibers. It is thus apparent that while, as a rule, uniformly compressed boards are desired, this device makes it possible to provide boards the edges of which are of greater density, should this be desired by a customer. Furthermore, this device serves as :a counter balance to the general tendency of the machine to collect more elongated fibers at the middle than at the edges.

As also to be seen from FIG. 3, the spot where the material is filled into the mould is at both longitudinal sides-limited by vertical walls 9a, 9b below which tight and inclined surfaces 10a, 10b are provided slightly above the rims 19 which are moved on the conveyer belt 34.

The surfaces 10a, 10b extend at an acute angle for the length of the conveyer located between the lines A-A and B-B of FIG. 1, as illustrated in FIGS. 3 and 4.

The surfaces 10a, 10b extend vertically for the length of the conveyer located beyond the line CC in FIG. 1, as illustrated in FIG. 5. During the length of the conveyer between the lines BB and CC the surfaces 10a,

10b bend gradually from the angular position to the vertical position. Due to this arrangement there is an accumulation of material adjacent the surfaces 10a, 10b in front of the pressing device, which is partly moved away from the edges during the pressing. Without the use of the angular portions of the surfaces, there would not be enough fibrous material at the edges.

The walls 9a, 9b, the members 10a, Nb and the guide 3 carrying the rolls 4 are immovably fixed to the machine frame by any suitable means not illustrated. According to FIG. 11, the inclined surfaces 10a, 1% may instead be directly adjacent to the base 18 or a mould belt if the marginal rims 19 are left out.

With reference to FIG. 1 again, and following the advance direction 7 of the conveyer belt 34, a picker roll 11, being vertically adjustable, is positioned behind the distributor 2. FIGURE 4 reveals that this roll carries a plurality of rotating spikes or fingers which downwardly extend to the lowest portions'of surface of the material in the mould plates 18. The picker roll 11 has to serve three important purposes: it combs the material on the panels to receive a uniform distribution, it further orients the strands of fibre material in lengthwise direction, and also it distributes the mainly long strands picked up from the material evenly over its surface. The rotation of the picker roll 11 is in arrow direction of FIG. 1 so that its spikes or'fingers act on the fibre material in the mould plates 18 in advance direction of conveyer belt 34. With this rotating direction not only uni-form distribution of the material but also good interlacing of the strands with one another and thereby a high degree of breaking strength and elasticity of the finished boards is achieved.

Two fixed side walls 12 are mounted on the apparatus in advance direction behind the roll 11. They prevent materials from being spread otf sideways. Along the extension of these side walls 12 the surfaces 10a, 1% which were inclined in FIG. 3, are vertical (see FIG.

so that they serve to make the material denser in the marginal portion.

Farther following the moving direction of the materiai, a pressing device, for instance in the shape of two pressing rolls 13, 13a, is provided behind the walls 12.

The lower roll 13a has a fixed shaft and acts as a counterpressure roll. The upper roll 13 has a vertically adjustable shaft. The rolls 13, 13a are rotated by an electric motor 3-5 through a chain drive 36, the rotating direction is indicated by the arrows in FIG. 6. As FIG. 5 discloses, the upper roll 13 is guided without play by the two vertical side surfaces a, 10b, and the material which is accumulated here fortifies the marginal portions of .the board by the pressing process. The material in the mould plates 18 may be pressed slightly in excess of the thinness desired because, after leaving this pressing stage, the material is bound to expand a little.

After this procedure the pressed board is cut off by a circularsaw 24 which is movable with the mould plates. This part of the apparatus is described in detail and claimed in my copending patent application. The saw '24 extends slightly below the base surface of the mould plates 18, thus cutting a slot 21 into the edges of two abutting plates. The marginal rims 19 are shorter than the bottom 18 of the mould plates, therefore the saw 24 can freely be moved between the ends of the rim 19 adjacent each other. Passing the rolls 22 the separate boards arrive at a piling place, where they are piled up above one another for hardening, as this is shown in FIGS. 8 and 12..

FIG. .7 shows the device of speed regulation of conveyer belt 34 with its mould plates 18 in dependence of weight of the material given on the conveyer belt balance 1. The roll 25 in the rear of the balance belt 1 is rotatably mounted on its axis 26 and the frontal roll is supported by a bracket not shown in the drawing. The axis 26 is pivotally mounted and rigidly fixed to said bracket. A vertical bar 27 and a horizontal lever 28 also are rigidly secured to the axis 26. A balance-weight 29 which may be moveable is mounted on the horizontal lever 23, and a second balance weight, moveable as well, is carried by the vertical bar 27. A rope 31 at its top is in actionon the end of lever 28, farther downward it is Wound once around .a rope drum 32, while the lower end carries a weight 33. The drum 32 is connected, for instance, with the speed governor of an electric motor 35 by which the rolls 13, 13a and the conveyer belt 34 are driven, and which may be a three-phase alternating current shunt commutator motor. Instead thereof, the drum 32 may be coupled together with some regulative transmission or similar connections.

The moveable weight 30 may be replaced by some other means, such as a spring, which creates a force when the balance belt 1 is turned by which the desired regulation ofadvance movement of the conveyer belt 34 is achieved.

The balance belt '1 can be driven as it is most convenient in the individual case, for instance by a drum motor, or by a gearing motor. This driving motor may simultaneously be used toform the balance weight 29.

The operation of the speed regulation system is as follows: When more or more weighty material is given onto the conveyor belt balance 1 this turns in down- Ward direction toward a position marked in dotted lines in the drawing. Rod 27 and lever 28 follow this movement so that by the rope 31 the drum 32 is turned to a certain extent to effectuate an increase of speed of the motor 35. The adjustable balance weight 30 allows to adjust the weight of the 'building boards to be produced. When for instance the weight 30 on rod 27 is shifted in upward direction a comparatively little increase in weight causes a downward turn of the balance belt 1 and thus results in corresponding speed enhancement of conveyer belt 34. If otherwise the weight of the material drops below the desired amount, the speed of conveyer belt 34 is diminished.

According to FIG. 6 the motor 35, being regulated in the above described regulation system, is in direct connection with the press rolls 13, 13a by a chain 36 Whereas the drive for the conveyer belt 34 according to FIG. 1 is transmitted through the lower roll 13a by means of a chain conneetion 37 to the reardrivingroll of the conveyer. The common drive for conveyer belt 34 and press rolls 13, 13a asssurcs uniform speed of boththese parts of the apparatus. Instead of the press rolls 13, 13a other pressing means, for instance a plunger press, may be used.

In the embodiment of the invention shown in FIG. 1 the distributor wheel 2 is at its lower side lined with a sheet iron plate 17. Instead of this a rotating drum 38 as shown in FIG. 9 may be provided, which operates as an intermediary partbetween the balance belt 1 and the distributor wheel, thus preventing the material from iimnediately falling down onto the wheel.

In this modification the distributor wheel consists of two rolls 39 extending over the whole breadth of the mould plates, each of them of half the breadth and each of their respective shafts 40 being able to be turned around a point 41. The more the rolls 39 are turned ofl? one another the more material is strew sideways, thus strengthening the marginal portions of the boards.

If the mould plates 18 are shaped without marginal rims 19"as in FIG. 11the single separated boards preferably are piled up above one another with their mould plates 18 with loose ledges 42put inbetween them. To

achieve sharp edges this pile is secured together in known manner by sideward plates 43 and vertical plates 44.

Instead of using the mould plates 18, it is possible to produce the boards directly on an endless belt, which is, for instance, of steel, which is advisable when using quickly hardening binding agents, such as magnesite.

It will be apparent from my foregoing specification that modifications may be made without departing from the spirit of my invention.

My claims are:

1. An apparatus for manufacturing light weight building boards from elongated wood wool fibers mixed with a binding agent, said apparatus comprising, in combination, a conveyer movable in a predetermined direction, forming plates carried by said conveyer and movable therewith, said forming plates having side rims, a distributor device located above said conveyer and rotatable in a direction opposite to the direction of movement of the conveyer to throw the material to be processed in said opposite direction upon the forming plates, a fixed guide shield located above said conveyer between the side rims of the forming plates and spaced from said distributor device in said opposite direction for receiving the material thrown by said distributor device, rolls connected with said guide shield for laterally compressing the material in the marginal spaces between said guide shield and said side rims, and a vertically adjustable picker roll located above said conveyer and spaced from said distributor device, said picker roll having a lower portion rotatable in the direction of movement of said conveyor and being adapted to engage the material carried by said forming plates.

2. An apparatus for manufacturing light weight building boards from elongated wood wool fibers mixed with a binding agent, said apparatus comprising, in combination, a conveyor, forming plates carried by said conveyer and movable therewith, a distributor device located above said conveyor for throwing the material to be processed upon said forming plates, a vertically adjustable picker roll located above said conveyer and spaced from said distributor device, said picker roll having a lower portion rotatable in the direction of movement of said conveyer and being adapted to engage the material carried by said forming plates, a pressing device located above said conveyer and spaced from said picker roll for compressing the material thrust by the picker roll, said picker roll being located between said distributor device and said pressing device, and means forming stationary surfaces located on opposite sides of said forming plates and constituting side walls holding the material carried by said forming plates, said stationary surfaces being outwardly inclined adjacent said distributor device and said picker roll and being vertical adjacent said pressing device and engaging said pressing device.

3. An apparatus in accordance with claim 2, wherein said distributor device comprises two rolls located side by side, horizontal shafts carrying said rolls, and vertical pivots swingably supporting said shafts and located outside of said forming plates for varying the direction of pressure exerted by said rolls upon the material to be processed.

4. An apparatus for manufacturing light weight building boards from elongated wood wool fibers mixed with a binding agent, said apparatus comprising, in combination, a conveyer, forming plates carried by said conveyer and movable therewith, said forming plates having side rims, a distributor device located above said conveyor for throwing the material to be processed upon said forming plates, :1 fixed guide shield located above said conveyor between the side rims of the forming plates and spaced from said distributor device, said guide shield having a curved surface for receiving the material thrown by said distributor device, rotary rolls having vertical axes, means carried by said guide shield and resiliently supporting said rolls adjacent said side rims, said rolls compressing the material in the marginal spaces between said guide shield and said side rims, a vertically adjustable picker roll located above said conveyor and spaced from said distributor device, said picker roll having a lower portion rotatable in the direction of movement of said conveyer and being adapted to engage the material carried by said forming plates, and a pressing device located above said conveyer and spaced from said picker roll, said picker roll being located between said distributor device and said pressing device.

References Cited in the file of this patent UNITED STATES PATENTS 2,165,280 Lannan July 11, 1939 2,377,484 Elmendorf June 5, 1945 2,737,997 Himmelheber et a1 Mar. 3, 1956 2,743,758 Uschmann May 1, 1956 2,822,024 Himmelheber et al. Feb. 4, 1958 2,822,028 Himmelheber et a1. Mar. 4, 1958 

1. AN APPARATUS FOR MANUFACTURING LIGHT WEIGHT BUILDING BOARDS FROM ELONGATED WOOD WOOL FIBERS MIXED WITH A BINDING AGENT, SAID APPARATUS COMPRISING, IN COMBINATION, A CONVEYER MOVABLE IN A PREDETERMINED DIRECTION, FORMING PLATES CARRIED BY SAID CONVEYER AND MOVABLE THEREWITH, SAID FORMING PLATES HAVING SIDE RIMS, A DISTRIBUTOR DEVICE LOCATED ABOVE SAID CONVEYER AND ROTABLE IN A DIRECTION OPPOSITE TO THE DIRECTION OF MOVEMENT OF THE CONVEYER TO THROW THE MATERIAL TO BE PROCESSED IN SAID OPPOSITE DIRECTION UPON THE FORMING PLATES, A FIXED GUIDE SHIELD LOACTED ABOVE SAID CONVEYER BETWEEN THE SIDE RIMS OF THE FORMING PLATES AND SPACED FROM SAID DISTRIBUTOR DEVICE IN SAID OPPOSITE DIRECTION FOR RECEIVING THE MATERIAL THROUWN BY SAID DISTRIBUTOR DEVICE, ROLLS CONNECTED WITH SAID GUIDE SHIELD FOR LATERALLY COMPRESSING THE MATERIAL IN THE MARGINAL SPACES BETWEEN SAID GUIDE SHIELD AND SAID SIDE RIMS, AND A VERTICALLY ADJUSTABLE PICKER ROLL LOCATED ABOVE SAID CONVEYER AND SPACED FROM SAID DISTRIBUTOR DEVICE, SAID PICKER ROLL HAVING A LOWER PORTION ROTATABLE IN THE DIRECTION OF MOVEMENT OF SAID CONVEYOR AND BEING ADAPTED TO ENGAGE THE MATERIAL CARRIED BY SAID FORMING PLATES. 